Objectsand Variablesmay change their Attributevalues after being created. Special rules apply for some Attributesas defined in 6.2.6.

Additional Referencesmay be added to the Nodes, and Referencesmay be deleted as long as the ModellingRulesdefined on the InstanceDeclarationsof the TypeDefinitionNodeare still fulfilled.

For Variablesand Objectsthe HasTypeDefinition Referenceshall always point to the same TypeDefinitionNodeas the InstanceDeclarationor a subtype of it.

If two InstanceDeclarationsof the fully-inherited InstanceDeclarationHierarchyhave been connected directly with several References, all those Referencesshall connect the same Nodes. An example is given in Figure 23. The instances A1 and A2 are allowed since B1 references the same Nodewith both References, whereas A3 is not allowed since two different Nodesare referenced. Note that this restriction only applies for directly connected Nodes. For example, A2 references a C1 directly and a different C1 via B1.


Figure 23– Example for several References between InstanceDeclarations